1. Field of the Invention
The present invention relates to semiconductor wafer processing, LCD display glass substrate processing, magnetic memory disc processing, and other devices fabricated from thin film processes, and, more specifically, to a system that can sense and record processing conditions and transmit data to a receiver.
2. Discussion of the Related Art
The fabrication of an integrated circuit, display or disc memory generally employs numerous processing steps. Each process step must be carefully monitored in order to provide an operational device. Throughout the imaging process, deposition and growth process, etching and masking process, etc., it is critical, for example, that temperature, gas flow, vacuum, pressure, chemical, gas or plasma composition and exposure distance be carefully controlled during each step. Careful attention to the various processing conditions involved in each step is a requirement of optimal semiconductor or thin film processes. Any deviation from optimal processing conditions may cause the ensuing integrated circuit or device to perform at a substandard level or, worse yet, fail completely.
Within a processing chamber, processing conditions vary. The variations in processing conditions such as temperature, gas flow rate and/or gas composition greatly affect the formation and, thus, the performance of the integrated circuit. Using a substrate to measure the processing conditions that is of the same or similar material as the integrated circuit or other device provides the most accurate measure of the conditions because the material properties of the substrate is the same as the actual circuits that will be processed. Gradients and variations exist throughout the chamber for virtually all process conditions. These gradients, therefore, also exist across the surface of a substrate, as well as below and above it. In order to precisely control processing conditions at the wafer, it is critical that measurements be taken upon the wafer and the readings be available in real time to an automated control system or operator so that the optimization of the chamber processing conditions can be readily achieved. Processing conditions include any parameter used to control semiconductor or other device fabrication or any condition a manufacturer would desire to monitor.
Within the processing chamber a robot transports the test wafer or substrate. One example of a device incorporating a robot is manufactured by the TEL Corporation. For more information about the robot and processing chamber, please refer to U.S. Pat. No. 5,564,889 to Araki, entitled “Semiconductor Treatment System and Method for Exchanging and Treating Substrate,” which is hereby incorporated by this reference in its entirety.